Pocket Electronics Swiss Army Knife

#include <Arduino.h>
#include <Wire.h>
#include <WiFi.h>
#include <math.h>
#include <driver/i2s.h>
#include <Adafruit_BME680.h>
#include <SparkFun_SCD4x_Arduino_Library.h>
#include <BH1750.h>
#include <Adafruit_BNO055.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_PN532.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <IRremoteESP8266.h>
#include <IRsend.h>
#include <NimBLEDevice.h>

constexpr int I2C_SDA = 8;
constexpr int I2C_SCL = 9;
constexpr int I2S_BCLK = 4;
constexpr int I2S_WS = 5;
constexpr int MIC_DATA = 6;
constexpr int AMP_DATA = 7;
constexpr int IR_PIN = 14;
constexpr int WHITE_LED_PIN = 1;
constexpr int RED_LED_PIN = 2;
constexpr int UV_LED_PIN = 3;
constexpr int NEXT_BUTTON_PIN = 15;
constexpr int ACTION_BUTTON_PIN = 16;
constexpr int TORCH_BUTTON_PIN = 17;
constexpr uint8_t PM_I2C_ADDRESS = 0x12;

Adafruit_BME680 bme;
SCD4x scd4x;
BH1750 lightMeter;
Adafruit_BNO055 bno(55, 0x28, &Wire);
// This PN532 breakout is used in I2C mode; IRQ and reset are not wired.
Adafruit_PN532 nfc(0xFF, 0xFF, &Wire);
Adafruit_SSD1306 display(128, 64, &Wire, -1);
IRsend irsend(IR_PIN);

bool bmeReady = false;
bool scdReady = false;
bool bnoReady = false;
bool nfcReady = false;
uint8_t page = 0;
uint8_t torchMode = 0;
uint32_t lastSensorRead = 0;
uint32_t lastNfcRead = 0;
uint32_t lastButtonChange = 0;
float temperatureC = NAN;
float humidity = NAN;
float gasKohm = NAN;
uint16_t co2ppm = 0;
uint16_t pm25 = 0;
float lux = NAN;
float heading = NAN;
float roll = NAN;
float pitch = NAN;
float soundDbfs = NAN;
String nfcUid = "No tag";
String radioStatus = "Press ACT to scan";

bool pressed(int pin) {
  if (digitalRead(pin) == LOW && millis() - lastButtonChange > 180) {
    lastButtonChange = millis();
    return true;
  }
  return false;
}

void setTorch() {
  uint8_t white = 0;
  uint8_t red = 0;
  uint8_t uv = 0;
  if (torchMode == 1) white = 45;
  if (torchMode == 2) white = 120;
  if (torchMode == 3) white = 255;
  if (torchMode == 4) red = 100;
  if (torchMode == 5) uv = 80;
  ledcWrite(WHITE_LED_PIN, white);
  ledcWrite(RED_LED_PIN, red);
  ledcWrite(UV_LED_PIN, uv);
}

void startAudio() {
  i2s_config_t config = {};
  config.mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX | I2S_MODE_RX);
  config.sample_rate = 16000;
  config.bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT;
  config.channel_format = I2S_CHANNEL_FMT_ONLY_LEFT;
  config.communication_format = I2S_COMM_FORMAT_STAND_I2S;
  config.intr_alloc_flags = 0;
  config.dma_buf_count = 8;
  config.dma_buf_len = 64;
  config.use_apll = false;
  config.tx_desc_auto_clear = true;
  config.fixed_mclk = 0;
  i2s_pin_config_t pins = {};
  pins.bck_io_num = I2S_BCLK;
  pins.ws_io_num = I2S_WS;
  pins.data_out_num = AMP_DATA;
  pins.data_in_num = MIC_DATA;
  i2s_driver_install(I2S_NUM_0, &config, 0, nullptr);
  i2s_set_pin(I2S_NUM_0, &pins);
  i2s_zero_dma_buffer(I2S_NUM_0);
}

void measureSound() {
  int32_t samples[128];
  size_t bytesRead = 0;
  i2s_read(I2S_NUM_0, samples, sizeof(samples), &bytesRead, 25 / portTICK_PERIOD_MS);
  int count = bytesRead / sizeof(int32_t);
  if (count < 1) return;
  double meanSquare = 0.0;
  for (int i = 0; i < count; ++i) {
    int32_t sample = samples[i] >> 8;
    meanSquare += (double)sample * (double)sample;
  }
  double rms = sqrt(meanSquare / count);
  soundDbfs = (float)(20.0 * log10((rms + 1.0) / 8388607.0) + 94.0);
}

void playTone() {
  const int sampleRate = 16000;
  const int frequency = 880;
  const int samples = sampleRate / 6;
  int32_t frame[32];
  for (int offset = 0; offset < samples; offset += 32) {
    for (int i = 0; i < 32; ++i) {
      float phase = 2.0f * PI * frequency * (offset + i) / sampleRate;
      frame[i] = (int32_t)(sinf(phase) * 500000000.0f);
    }
    size_t written = 0;
    i2s_write(I2S_NUM_0, frame, sizeof(frame), &written, portMAX_DELAY);
  }
  i2s_zero_dma_buffer(I2S_NUM_0);
}

bool readPm25() {
  Wire.requestFrom((int)PM_I2C_ADDRESS, 32);
  if (Wire.available() < 32) return false;
  uint8_t data[32];
  for (uint8_t i = 0; i < 32; ++i) data[i] = Wire.read();
  if (data[0] != 0x42 || data[1] != 0x4D) return false;
  pm25 = ((uint16_t)data[12] << 8) | data[13];
  return true;
}

void readSensors() {
  if (bmeReady && bme.performReading()) {
    temperatureC = bme.temperature;
    humidity = bme.humidity;
    gasKohm = bme.gas_resistance / 1000.0f;
  }
  if (scdReady && scd4x.readMeasurement()) {
    co2ppm = scd4x.getCO2();
  }
  readPm25();
  lux = lightMeter.readLightLevel();
  if (bnoReady) {
    sensors_event_t event;
    bno.getEvent(&event, Adafruit_BNO055::VECTOR_EULER);
    heading = event.orientation.x;
    roll = event.orientation.y;
    pitch = event.orientation.z;
  }
  measureSound();
}

void scanNfc() {
  if (!nfcReady) return;
  uint8_t uid[7];
  uint8_t uidLength = 0;
  if (nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, uid, &uidLength, 50)) {
    nfcUid = "UID ";
    for (uint8_t i = 0; i < uidLength; ++i) {
      if (uid[i] < 16) nfcUid += "0";
      nfcUid += String(uid[i], HEX);
    }
    nfcUid.toUpperCase();
  }
}

void scanRadios() {
  int wifiCount = WiFi.scanNetworks(false, true);
  if (wifiCount < 0) wifiCount = 0;
  NimBLEDevice::init("");
  NimBLEScan *scanner = NimBLEDevice::getScan();
  scanner->setActiveScan(true);
  NimBLEScanResults results = scanner->getResults(2000, false);
  int bleCount = results.getCount();
  scanner->clearResults();
  NimBLEDevice::deinit(true);
  WiFi.scanDelete();
  radioStatus = "WiFi " + String(wifiCount) + " BLE " + String(bleCount);
}

void drawScreen() {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setTextSize(1);
  if (page == 0) {
    display.setCursor(0, 0); display.println("AIR QUALITY");
    display.printf("CO2: %u ppm\n", co2ppm);
    display.printf("PM2.5: %u ug/m3\n", pm25);
    display.printf("T: %.1f C  H: %.0f%%\n", temperatureC, humidity);
    display.printf("VOC gas: %.0f kOhm\n", gasKohm);
    display.println("BME gas is a VOC trend");
  } else if (page == 1) {
    display.setCursor(0, 0); display.println("LEVEL / SOUND");
    display.printf("Heading: %.0f deg\n", heading);
    display.printf("Roll: %.1f  Pitch: %.1f\n", roll, pitch);
    display.printf("Light: %.0f lux\n", lux);
    display.printf("Sound: %.0f dBFS*\n", soundDbfs);
    display.println("*relative; calibrate for dB");
  } else if (page == 2) {
    display.setCursor(0, 0); display.println("NFC / RADIO SCAN");
    display.println(nfcUid);
    display.println(radioStatus);
    display.println("ACT scans WiFi + BLE");
    display.println("Hold a tag near NFC pad");
  } else {
    display.setCursor(0, 0); display.println("TOOLS");
    const char *names[] = {"OFF", "WHITE LOW", "WHITE MID", "WHITE HIGH", "RED", "UV"};
    display.print("Torch: "); display.println(names[torchMode]);
    display.println("ACT: IR test + tone");
    display.println("Torch button changes mode");
    display.println("IR code: NEC 20DF10EF");
  }
  display.display();
}

void setup() {
  Serial.begin(115200);
  Wire.begin(I2C_SDA, I2C_SCL);
  pinMode(NEXT_BUTTON_PIN, INPUT_PULLUP);
  pinMode(ACTION_BUTTON_PIN, INPUT_PULLUP);
  pinMode(TORCH_BUTTON_PIN, INPUT_PULLUP);
  ledcAttach(WHITE_LED_PIN, 5000, 8);
  ledcAttach(RED_LED_PIN, 5000, 8);
  ledcAttach(UV_LED_PIN, 5000, 8);
  setTorch();
  irsend.begin();
  startAudio();
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.clearDisplay(); display.display();
  bmeReady = bme.begin(0x76, &Wire);
  lightMeter.begin(BH1750::CONTINUOUS_HIGH_RES_MODE, 0x23, &Wire);
  scdReady = scd4x.begin(Wire);
  if (scdReady) scdReady = scd4x.startPeriodicMeasurement();
  bnoReady = bno.begin();
  if (bnoReady) bno.setExtCrystalUse(true);
  nfc.begin();
  uint32_t version = nfc.getFirmwareVersion();
  nfcReady = version != 0;
  if (nfcReady) nfc.SAMConfig();
  drawScreen();
}

void loop() {
  bool changed = false;
  if (pressed(NEXT_BUTTON_PIN)) {
    page = (page + 1) % 4;
    changed = true;
  }
  if (pressed(TORCH_BUTTON_PIN)) {
    torchMode = (torchMode + 1) % 6;
    setTorch();
    changed = true;
  }
  if (pressed(ACTION_BUTTON_PIN)) {
    if (page == 2) scanRadios();
    if (page == 3) {
      irsend.sendNEC(0x20DF10EF, 32);
      playTone();
    }
    changed = true;
  }
  if (millis() - lastSensorRead >= 1000) {
    lastSensorRead = millis();
    readSensors();
    changed = true;
  }
  if (page == 2 && millis() - lastNfcRead >= 750) {
    lastNfcRead = millis();
    String before = nfcUid;
    scanNfc();
    if (before != nfcUid) changed = true;
  }
  if (changed) drawScreen();
  delay(10);
}